The changes come after a passenger, Dr. David Dao, was dragged from a fully-booked United Express flight in Chicago because he refused to give up his seat to make room for crew members. Cellphone video of the incident sparked widespread outrage and created a public-relations nightmare for United.

Under the change outlined in an internal United Airlines April 14 email, a crew member is required to make must-ride bookings at least 60 minutes prior to departure. Previously, crews could be booked until the time of departure.

United spokeswoman Maggie Schmerin said in an email Sunday that the change is an initial step in a review of policies and is meant to ensure that situations like Dao’s never happen again.

“Will there be a lawsuit? Probably,” said Thomas Demetrio, one of the two aviation lawyers representing Dao. He hinted there could be multiple defendants, saying “just because United is responsible, doesn’t mean the city of Chicago isn’t responsible.”

In a statement last week, United apologized to Dao and detailed changes it was making, including no longer using law enforcement officers to take passengers off a flight and reviewing policies and training programs.

“We continue to express our sincerest apology to Dr. Dao. We cannot stress enough that we remain steadfast in our commitment to make this right,” the statement said, in part. “This horrible situation has provided a harsh learning experience from which we will take immediate, concrete action. We have committed to our customers and our employees that we are going to fix what’s broken so this never happens again.”

In a video posted online, United Airlines passenger David Dao is shown with a bloody face after he was forced off an overbooked flight on Sun., April 9, 2017, by officers at Chicago O’Hare airport.